The present invention relates to basic aluminum antiperspirant active materials having enhanced antiperspirant activity, antiperspirant active compositions including such basic aluminum antiperspirant active materials and also containing zirconium, hafnium, titanium and/or tin antiperspirant active materials, and methods of producing such materials and compositions. Moreover, the present invention is directed to basic aluminum antiperspirant active materials (polymeric species of basic aluminum compounds) and antiperspirant active compositions containing such materials, having enhanced antiperspirant activity, which can be produced under conditions much less severe than those utilized in producing conventional basic aluminum materials and compositions with enhanced antiperspirant activity, and which are more stable in aqueous solution than conventional basic aluminum materials and compositions having enhanced antiperspirant efficacy. The materials and compositions of the present invention have a wide range of application as antiperspirant materials, including, for example, as antiperspirant materials in aerosols, roll-ons, solid stick antiperspirants, etc.
It has been desired to provide improved antiperspirant active materials, having enhanced antiperspirant activity. British Patent Specification No. 1,568,831 describes enhanced efficacy antiperspirant materials, employing certain basic aluminum chloride, bromide, iodide and nitrate compounds, with modification of such compounds in aqueous solution such that the materials include aqueous solutions of polymeric species (of such compounds) having a size greater than 100 .ANG., in which species having a size greater than 100 .ANG. there is contained from 2-80% by weight of the total aluminum in solution. This British patent discloses that the basic aluminum compound may have the empirical formula Al.sub.2 (OH).sub.6-a X.sub.a, where X is Cl, Br, I or NO.sub.3 and a is from 0.4 to 1.5. This patent discloses that the modified basic aluminum compounds which in aqueous solution contain polymeric species having a size greater than 100 .ANG. may be prepared by heating aqueous solutions of the basic aluminum compounds at elevated temperatures, preferably 80.degree. C. to 140.degree. C., for periods of 0.5 hour to 30 days (the period of heating being shorter at higher temperatures).
In Example 14 of this British patent, there is disclosed preparation of a basic aluminum nitrate to form the disclosed enhanced efficacy antiperspirant materials. Specifically, an aluminum nitrate nonahydrate solution was prepared and then heated to 90.degree. C. under a reflux condenser, with aluminum powder being added in small portions and heating then being continued with stirring; thereafter, the solution was cooled to room temperature and filtered to remove excess aluminum, so as to provide the described aqueous solutions of the basic aluminum nitrate. The contents of British Patent Specification No. 1,568,831 are incorporated herein by reference in their entirety.
While British Patent Specification No. 1,568,831 discloses modified nitrate-containing basic aluminum compounds having enhanced antiperspirant activity, this patent focuses on modified compounds which form polymer species of a size greater than 100 .ANG. in aqueous solution. Moreover, in the example utilizing basic aluminum nitrate, heating is performed at relatively high temperatures of 90.degree. C. and for relatively long time periods of 29 hours. Neither the compounds or methods disclosed in this British Patent Specification No. 1,568,831 achieves the objectives of the present invention.
U.S. Pat. No. 4,359,456 discloses an improved antiperspirant active material, and methods for its preparation, the material comprising a polymeric aluminum compound having the empirical formula Al.sub.2 (OH).sub.6-a X.sub.a, wherein X is Cl, Br or I, a is about 0.3 to about 4, and wherein the antiperspirant active material is further characterized by: (a) a Size Exclusion Chromatography Test band having a relative retention time corresponding to Band III of the Standard Basic Aluminum Chloride Solution Size Exclusion Chromatogram; and (b) a Band III Percent Aluminum Value of at least 20%. This patent discloses that the enhanced antiperspirant effectiveness is related to the presence of a particular band (Band III) detected in the Size Exclusion Chromatography test, and that enhancement of the antiperspirant activity of the basic aluminum halide compounds having the empirical formula Al.sub.2 (OH).sub.6-a X.sub.a is achieved by increasing the aluminum content in the Band III fraction.
This U.S. Pat. No. 4,359,456 specifies that the basic aluminum halide compounds can be modified to provide enhanced activity antiperspirant materials by heating aqueous solutions of the basic aluminum halide compounds at elevated temperatures. Specifically, this patent discloses heating the aqueous solutions at temperatures of from 50.degree. C. to 140.degree. C., the period of heating being for periods of 0.5 hour to 30 days, depending on the temperature used (the period of heating being shorter when high temperatures are used). This patent also discloses that the concentration of the basic aluminum compound in the solution is important, with the aluminum concentration of the solution of the basic aluminum compound to be treated ranging from 2.5% to 8.5% by weight. This U.S. Pat. No. 4,359,456 additionally specifies that the aqueous solution of the enhanced activity antiperspirant compound comprising the Band III polymeric species may, if desired, be dried to give the compound the form of a solid hydrate, and that spray-drying may be a particularly useful method for such drying to provide the solid hydrate. This patent further discloses that the enhanced activity antiperspirant material described therein can be incorporated with various materials, such as a perfume, thickener, alcohol or propellant, to provide antiperspirant compositions. The contents of U.S. Pat. No. 4,359,456, including the description therein of various materials with which the modified, antiperspirant active compound can be combined to provide antiperspirant compositions, are incorporated herein by reference in their entirety.
While U.S. Pat. No. 4,359,456 discloses basic aluminum halide compounds treated to provide materials having enhanced antiperspirant activity, such technique described therein has various disadvantages. Initially, the enhanced antiperspirant active material disclosed therein is relatively unstable in concentrated aqueous solution, and loses its enhanced efficacy in relatively short periods of time. Furthermore, this patent discloses that a desirable heating temperature for modifying the basic aluminum halides is upwards of 140.degree. C.; as can be appreciated, the relatively high heating temperature increases the cost of manufacturing the antiperspirant. Moreover, since the process of this patent includes an additional manufacturing step of heating a previously manufactured commercial antiperspirant, this process decreases throughput and, therefore, increases manufacturing costs.
European Patent Application No. 183,171 describes a method of preparing an enhanced efficacy aluminum chlorhydrate antiperspirant active material, the aluminum chlorhydrate material formed, and antiperspirant compositions containing such aluminum chlorhydrate, wherein an aqueous solution containing about 40-50 wt. % of aluminum chlorhydrate is heated to a temperature of at least about 130.degree. C. for about one to twelve hours (the heating time being inversely proportional to temperature) in a closed vessel, and cooling the resulting product, to provide the aluminum chlorhydrate having enhanced antiperspirant activity. The aluminum chlorhydrate treated according to the disclosed method is represented by the empirical formula Al.sub.2 (OH).sub.6-x Cl.sub.x, wherein x is in the range of about 1 to 2. This European patent application discloses that the modified aluminum chlorhydrate having enhanced antiperspirant activity, formed as indicated herein, is characterized by a size exclusion chromatogram having a single major peak with a relative retention time at its apex of about 0.75-0.79, with the area under the peak indicating at least 60% of the aluminum-containing species is within the fraction represented by the major peak. This European patent application further discloses that the resulting aluminum chlorhydrate solid, after the described heat-treatment and drying, may be incorporated into various conventional antiperspirant forms such as solutions (aqueous, non-aqueous or alcoholic), aerosols, powders, sticks, lotions, roll-ons, gels, creams and the like, which may contain a variety of non-toxic, dermatologically acceptable moieties such as solvents, emollients, propellants, perfumes, etc.
This European Patent Application No. 183,171 describes aluminum chlorhydrate materials having enhanced antiperspirant activity, being formed by heating previously manufactured aluminum chlorhydrate, wherein it is disclosed that the preferred heating temperatures are relatively high temperatures. Furthermore, the enhanced active materials disclosed therein are relatively unstable in concentrated aqueous solution, and lose their enhanced efficacy in relatively short periods of time in solution. Moreover, relatively long periods of heating are required to achieve the enhanced antiperspirant active materials.
European Patent Application No. 191,628 discloses a process for preparing basic aluminum halides having good antiperspirant activities, wherein the aluminum: halogen molar ratio is from 1.7 to 2.2:1 and wherein at least 20% of the aluminum is contained in the Band III fraction, including (a) dissolving metallic aluminum in an aqueous starting solution of an aluminum compound selected from aluminum chloride and aluminum bromide, the starting solution being held at a temperature of about 50.degree. C. to about 105.degree. C. for a time just long enough to dissolve sufficient aluminum to produce an aqueous solution of a final basic aluminum halide having an aluminum: halide molar ratio in the range of 1.7:1 to 2.2:1, the concentration of the aluminum in the starting solution and the amount of aluminum dissolved being such that the aluminum concentration in the solution of the final basic aluminum halide is from 0.8% to about 6.75% by weight and the final basic aluminum halide has at least 20% of the aluminum contained in the Band III fraction; and (b) drying the solution of the final basic aluminum halide so as to give the final basic aluminum halide in the form of a hydrated powder having at least 20% of the aluminum contained in the Band III fraction. This European patent application further describes that an essential feature of the process is the use of proportions of reactants such that when the desired basic aluminum halide is formed, usually at the point when substantially all of the aluminum has dissolved, the aluminum concentration of that solution is relatively low and in the range 0.8% to 6.75% by weight. This patent application specifies that the reaction is most conveniently carried out at atmospheric pressure, although elevated pressures, for example, can be used.
In achieving the range of aluminum concentration of the desired basic aluminum halide, this European Patent Application No. 191,628 describes a process in which the aluminum concentration in the solution, prior to addition of metallic aluminum, is less than 1.0% and in which initial aluminum solution concentrations of 2.0% are not useful. Furthermore, the enhanced antiperspirant active materials disclosed therein are relatively unstable in concentrated aqueous solution, and lose their enhanced efficacy in solution in relatively short periods of time.
Aluminum antiperspirant active materials which are commercially available and which have been disclosed in the prior art, including improved antiperspirant active materials having enhanced antiperspirant activity, typically contain 75-95% Al.sup.c, 0-15% Al.sup.b and 0-15% Al.sup.a. In one embodiment of European Patent Application No. 191,628, an Al.sub.13 O.sub.40 polymeric species is disclosed which may (or may not) complex with the ferron reagent at a rate which is characteristic of Al.sup.b. In any case, the formation of Al.sub.13 O.sub.40 polymeric species is favored by lower temperatures and shorter reaction times, these shorter reaction times requiring the use of more reactive forms of aluminum metal, such as powders of high surface area, and the use of catalysts.
While each of the European Patent Application Nos. 183,171 and 191,628 are described as advances beyond the technique disclosed in U.S. Pat. No. 4,359,456, neither of the techniques or products disclosed in these European patent applications achieve the benefits of the present invention.
U.K. Patent Application No. 2,048,229 describes a group of complexes, referred to as Al.sup.c', which fall within the aluminum chlorhydroxides represented by the empirical formula Al.sub.2 (OH).sub.5 Cl, which is more efficacious as an antiperspirant. This U.K. Patent Application No. 2,048,229 discloses that the group of complexes is characterized by a diffusion constant in gel permeation chromatography characteristic of complexes of lower molecular sizes, referred to as Al.sup.b, and by reaction rates of complexation with a ferron reagent characteristic of complexes of the largest molecular sizes, referred to as Al.sup.c. This U.K. Patent Application No. 2,048,229 describes a method for aging presently available aluminum chlorhydroxide in an aqueous medium until the aluminum chlorhydroxide contains at least 45% of the Al.sup.c' group.
While U.K. Patent Application No. 2,048,229 discloses a basic aluminum chloride compound treated to provide material having enhanced antiperspirant activity, such material has the disadvantage of requiring relatively long aging periods or low concentrations for its preparation; as can be appreciated, the requirement of aging a previously manufactured basic aluminum chloride for relatively long time periods increases the cost of manufacturing the antiperspirant. Furthermore, this U.K. Patent Application No. 2,048,229 discloses that concentrated solutions of Al.sup.c' are not stable for extended periods. Neither the compounds or methods disclosed in this U.K. Patent Application No. 2,048,229 achieve the objectives of the present invention.
All the foregoing documents, apart from British patent specification No. 1,568,831, are directed to halide-containing aluminum materials, and do not disclose basic aluminum materials containing nitrates or other, univalent oxoanions. Moreover, as indicated in the foregoing, each of these materials have disadvantages and do not achieve the objectives of the present invention.
U.S. Pat. No. 4,859,446 to Abrutyn, et al discloses a process for preparing basic aluminum materials having the empirical formula Al.sub.2 (OH).sub.6-a X.sub.a, where a is about 1.0 to about 4, and X is Cl, Br, I, SO.sub.4 or NO.sub.2, with the materials having a Band III aluminum value of at least 40%, and preferably having a Band I value of not greater than 5%. The process includes reacting an aqueous solution of an aluminum compound of the empirical formula Al.sub.n X.sub.m, where n is 1 or 2 and m is 1 or 3, with aluminum metal at a temperature between 50.degree. and 195.degree. C., until a specific ratio of aluminum to anion is achieved. No mention is made of nitrate-containing basic aluminum material, or of any other univalent oxoanion (other than nitrite). Furthermore, the nitrite essentially forms no salts with Al.sup.3+ in aqueous solution. Moreover, while this patent discloses use of nitrous acid to produce the basic aluminum nitrite, no mention is made of utilizing nitric acid to produce a basic aluminum nitrate. The compounds according to this U.S. patent cannot achieve the objectives of the present invention.
Furthermore, it is also desired, as part of the present invention, to achieve an antiperspirant composition including an enhanced activity aluminum material and a zirconium, hafnium, tin and/or titanium antiperspirant material, which composition has good stability in aqueous solution and which can be manufactured without utilizing severe processing conditions (for example, without high temperatures and without high pressure conditions).
British Patent Specification No. 1,353,916 discloses aerosol antiperspirant powder spray compositions containing a powder antiperspirant active complex, formed by the steps of: (a) heating an aqueous solution containing from 1 to 3.2 parts by weight of aluminum chlorhydroxide to a temperature of from 190.degree. F. to 225.degree. F.; (b) adding an aqueous solution containing one part by weight of zirconyl hydroxychloride to the aluminum chlorhydroxide solution at such a rate that the addition takes from two hours to five hours, while heating and agitating, the total anhydrous solids content when all of the zirconyl hydroxychloride has been added being at least 19% by weight; and (c) heating and agitating the aluminum chlorhydroxide/zirconyl hydroxychloride mixture at from 190.degree. F. to 225.degree. F. for from one-half hour to about five hours until a stable complex forms. This patent discloses that after forming the stable complex, the complex is dried to an impalpable powder. This patent discloses that the described process results in the production of a higher pH antiperspirant complex (for the same zirconium level as other materials) which is less irritating to the skin, less damaging to fabrics and less corrosive to packaging than conventional compositions; and that the complex also eliminates the need for the addition of buffering, anti-gelling and compatibilizer agents. This patent goes on to state that the dried powder can be incorporated in various powder aerosol antiperspirant compositions as the active material.
U.S. Pat. No. 4,223,010 discloses basic zirconium complexes, used in antiperspirants, formed by reacting acidic aluminum and/or zirconium compounds with a freshly prepared basic zirconium compound selected from basic zirconium-amino acid gels, zirconium hydroxide gels, basic zirconium carbonate gels and mixtures thereof, to form a complex having an Al/Zr molar ratio of about 10:1 to 1:10; this patent discloses that the complexes may be dried to a powder form and used in any of a wide variety of conventional antiperspirant forms, including lotions, creams, roll-ons, aerosol sprays and powder-in-oil aerosol sprays. This patent discloses that the acid aluminum compounds include aluminum halides, as well as other basic aluminum salts such as the nitrates, sulfamates, sulfates and mixtures thereof.
United Kingdom Patent Application No. 2,144,992 discloses a composition of zirconyl hydroxychloride and aluminum chlorhydroxide in stable solid form, having enhanced antiperspirant efficacy when dissolved in water, the composition being made by heating a 2-20% by weight aqueous solution of zirconyl hydroxychloride and aluminum chlorhydroxide at a temperature of at least 50.degree. C. until the ratio of the height of peak 4 to that of peak 3, as measured by gel permeation chromatography on cross-linked dextran, exceeds 2:1, then subjecting the solution to rapid drying to solid form. This United Kingdom patent application further discloses that the inclusion in the composition of a neutral amino acid does not have an adverse affect upon the formation of the desired complex, and does not interfere with the conversion of the heated solution to solid form nor with subsequent use of the solids as an antiperspirant. This United Kingdom patent application further discloses that the neutral amino acid (for example, glycine) aids in preventing gelation of the aqueous solution before or during the heating step.
Each of British Patent Specification No. 1,353,916 and British U.K. Patent Application No. 2,144,992 is directed to compositions including aluminum chlorhydroxide. Moreover, while U.S. Pat. No. 4,223,010 discloses use of various basic aluminum compounds, there is no disclosure that the aluminum has enhanced activity. Similarly, there is no disclosure in British Patent Specification No. 1,353,916 that the basic aluminum compound has enhanced activity. None of the compositions and methods disclosed in British Patent Specification No. 1,353,916, British Patent Application No. 2,144,992 and U.S. Pat. No. 4,223,010 achieves the objectives of the present invention.
U.S. Pat. No. 4,331,609 discloses antiperspirant aluminum and zirconium complexes including an aluminum compound, a zirconium compound, a neutral amino acid and an inorganic acidic compound. The aluminum compound has the empirical formula Al.sub.2 (OH).sub.6-n X.sub.n, wherein n has a value from about 0.80 to about 1.25 and X is selected from the group consisting of chlorine, bromine, iodine, sulfamate, sulfate, nitrate and mixtures thereof. The zirconium compound has the empirical formula ZrO(OH).sub.2-m Y.sub.m, wherein m has a value of from about 0.50 to about 1.5 and Y is selected from the group consisting of chlorine, bromine, iodine and mixtures thereof. The third component is an amino acid which is a water soluble neutral amino acid, a most preferred amino acid being glycine and other suitable amino acids being alanine, beta-alanine, methionine, tryptophan, beta-phenylalanine, serine, valine and two-amino-butyric acid. The fourth component is an inorganic acid compound selected from the group consisting of aluminum chloride, hydrochloric acid and mixtures thereof. The complex should have an aluminum to zirconium molar ratio from about 2 to about 10, and the neutral amino acid should be present in the antiperspirant complex in such an amount that the molar ratio of neutral amino acid to total metal is from about 0.09 to about 0.24.
U.S. Pat. No. 2,814,584 discloses an antiperspirant composition including in combination an aqueous solution of a zirconium or hafnium salt of a strong monobasic mineral acid, a basic aluminum compound and urea. This patent discloses that while compounds of zirconium are relatively highly acidic and cannot therefore safely be used alone in contact with the skin, aqueous solutions of zirconium salts and hafnium salts, of strong monobasic mineral acids, may be rendered usable by treating them with certain basic aluminum compounds and urea, the basic aluminum compounds and the urea acting as buffering agents to bring the pH of the solution of the zirconium of hafnium salt to a value which renders it safe for antiperspirant usage. The zirconium and hafnium compounds which may be used, according to U.S. Pat. No. 2,814,584, are the chlorides, bromides, iodides and nitrates; the basic aluminum compounds which may be used have the general empirical formula Al.sub.2 (OH).sub.6-n X.sub.n, where X is a monovalent acid anion of the group Cl.sup.-, Br.sup.-, I.sup.- and NO.sub.3.sup.-, and n has an average value from about 0.8 to about 2.
U.S. Pat. No. 2,814,585 discloses antiperspirant compositions including in combination an aqueous solution of a zirconium or hafnium salt of a strong monobasic mineral acid, a basic aluminum compound and an amino acid in which the number of amino groups is equal to the number of carboxyl groups in the molecule. The zirconium and hafnium compounds may be chlorides, bromides, iodides and nitrates. The basic aluminum compounds can have a general empirical formula Al.sub.2 (OH).sub.6-n X.sub.n, where X is a monovalent acid anion of the group Cl.sup.-, Br.sup.-, I.sup.- and NO.sub.3.sup.-, and n has an average value from about 0.8 to about 2. This patent discloses that while the compounds of zirconium and hafnium are relatively highly acidic and cannot safely be used alone in contact with the skin, aqueous solutions of such zirconium and hafnium salts may be rendered usable by treating them with the basic aluminum compounds and amino acids, such compounds and acids acting as buffering agents to bring the pH of the solution of the zirconium or hafnium salt to a value which renders it safe for antiperspirant uses.
While each of U.S. Pat. No. 4,331,609, U.S. Pat. No. 2,814,584 and U.S. Pat. No. 2,814,585 describe antiperspirant compositions including at least a basic aluminum compound, which can be a basic aluminum nitrate, as well as a zirconium compound, these patents do not disclose use of basic aluminum and/or zirconium compounds of enhanced efficacy. In addition, these patents disclose generally the use of nitrates among other anions and do not describe any benefits or advantages achieved utilizing nitrates, specifically, as compared to, e.g., halides; in fact, these patents disclose that the nitrates therein are equivalent to, e.g., the chlorides. Moreover, these patents do not disclose use of other oxoanions (e.g., univalent oxoanions) as part of the basic aluminum and/or zirconium compound of the antiperspirant composition. Furthermore, U.S. Pat. No. 4,331,609 only discloses use of a basic zirconium halide, and does not teach use of basic zirconium compounds containing a univalent complex oxoanion such as nitrate. None of these U.S. patents achieve the objectives of the present invention.
U.S. Pat. No. 4,606,915 discloses a composition of a stannic halide and an aluminum halohydrate and also preferably containing a neutral amino acid, being useful in inhibiting perspiration when applied to the skin of a subject in powder form or when incorporated in a liquid or solid vehicle. In this patent, there is no disclosure that the aluminum has enhanced activity, nor that the resultant basic tin/aluminum halohydrate demonstrates enhanced antiperspirant activity. The contents of U.S. Pat. No. 4,606,915 are incorporated herein by reference in their entirety.
Accordingly, it is still desired to provide basic aluminum materials with enhanced antiperspirant activity; and compositions of (1) zirconium, hafnium, tin and/or titanium active antiperspirant material, either those conventionally known or those having enhanced antiperspirant activity, with (2) basic aluminum material having enhanced antiperspirant activity; which material and composition can be made without high temperatures and/or high pressures, and without the need for extra manufacturing steps of heating diluted solutions of already manufactured basic aluminum compounds. There is also still a need to provide basic aluminum antiperspirant materials with enhanced activity, and compositions containing the same, which can be provided in concentrated aqueous solutions, with improved compositional stability (that is, wherein the enhanced activity is not substantially reduced over a period of time).